/***************************************************************************
 *                                  _   _ ____  _
 *  Project                     ___| | | |  _ \| |
 *                             / __| | | | |_) | |
 *                            | (__| |_| |  _ <| |___
 *                             \___|\___/|_| \_\_____|
 *
 * Copyright (C) 1998 - 2008, Daniel Stenberg, <daniel@haxx.se>, et al.
 *
 * This software is licensed as described in the file COPYING, which
 * you should have received as part of this distribution. The terms
 * are also available at http://curl.haxx.se/docs/copyright.html.
 *
 * You may opt to use, copy, modify, merge, publish, distribute and/or sell
 * copies of the Software, and permit persons to whom the Software is
 * furnished to do so, under the terms of the COPYING file.
 *
 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
 * KIND, either express or implied.
 *
 * $Id: hostip6.c,v 1.47 2008-10-30 19:02:23 yangtse Exp $
 ***************************************************************************/

#include "setup.h"


#ifdef NEED_MALLOC_H
#include <malloc.h>
#endif
#ifdef HAVE_SYS_SOCKET_H
#include <sys/socket.h>
#endif
#ifdef HAVE_NETINET_IN_H
#include <netinet/in.h>
#endif
#ifdef HAVE_NETDB_H
#include <netdb.h>
#endif
#ifdef HAVE_ARPA_INET_H
#include <arpa/inet.h>
#endif
#ifdef HAVE_STDLIB_H
#include <stdlib.h>     /* required for free() prototypes */
#endif
#ifdef HAVE_UNISTD_H
#include <unistd.h>     /* for the close() proto */
#endif
#ifdef  VMS
#include <in.h>
#include <inet.h>
#include <stdlib.h>
#endif

#ifdef HAVE_PROCESS_H
#include <process.h>
#endif

#include "urldata.h"
#include "sendf.h"
#include "hostip.h"
#include "hash.h"
#include "share.h"
#include "strerror.h"
#include "url.h"
#include "inet_pton.h"
#include "connect.h"

#define _MPRINTF_REPLACE /* use our functions only */
#include <api/libcurl/mprintf.h>

#include "memory.h"
/* The last #include file should be: */
#include "memdebug.h"

/***********************************************************************
 * Only for ipv6-enabled builds
 **********************************************************************/
#ifdef CURLRES_IPV6

#ifndef CURLRES_ARES
#ifdef CURLRES_ASYNCH
/*
 * Curl_addrinfo_copy() is used by the asynch callback to copy a given
 * address. But this is an ipv6 build and then we don't copy the address, we
 * just return the same pointer!
 */
Curl_addrinfo *Curl_addrinfo_copy(const void *orig, int port)
{
	(void) port;
	return (Curl_addrinfo*)orig;
}
#endif  /* CURLRES_ASYNCH */
#endif  /* CURLRES_ARES */

#if defined(CURLDEBUG) && defined(HAVE_GETNAMEINFO)
/* These are strictly for memory tracing and are using the same style as the
 * family otherwise present in memdebug.c. I put these ones here since they
 * require a bunch of structs I didn't wanna include in memdebug.c
 */

/*
 * For CURLRES_ARS, this should be written using ares_gethostbyaddr()
 * (ignoring the fact c-ares doesn't return 'serv').
 */

int curl_dogetnameinfo(GETNAMEINFO_QUAL_ARG1 GETNAMEINFO_TYPE_ARG1 sa,
					   GETNAMEINFO_TYPE_ARG2 salen,
					   char *host, GETNAMEINFO_TYPE_ARG46 hostlen,
					   char *serv, GETNAMEINFO_TYPE_ARG46 servlen,
					   GETNAMEINFO_TYPE_ARG7 flags,
					   int line, const char *source)
{
	int res = (getnameinfo)(sa, salen,
							host, hostlen,
							serv, servlen,
							flags);
	if (0 == res)
	{
		/* success */
		if (logfile)
			fprintf(logfile, "GETNAME %s:%d getnameinfo()\n",
					source, line);
	}
	else
	{
		if (logfile)
			fprintf(logfile, "GETNAME %s:%d getnameinfo() failed = %d\n",
					source, line, res);
	}
	return res;
}
#endif /* defined(CURLDEBUG) && defined(HAVE_GETNAMEINFO) */

/*
 * Curl_ipvalid() checks what CURL_IPRESOLVE_* requirements that might've
 * been set and returns TRUE if they are OK.
 */
bool Curl_ipvalid(struct SessionHandle *data)
{
	if (data->set.ip_version == CURL_IPRESOLVE_V6)
	{
		/* see if we have an IPv6 stack */
		curl_socket_t s = socket(PF_INET6, SOCK_DGRAM, 0);
		if (s == CURL_SOCKET_BAD)
			/* an ipv6 address was requested and we can't get/use one */
			return FALSE;
		sclose(s);
	}
	return TRUE;
}

#if !defined(USE_THREADING_GETADDRINFO) && !defined(CURLRES_ARES)

#ifdef DEBUG_ADDRINFO
static void dump_addrinfo(struct connectdata *conn, const Curl_addrinfo *ai)
{
	printf("dump_addrinfo:\n");
	for ( ; ai; ai = ai->ai_next)
	{
		char  buf[INET6_ADDRSTRLEN];

		printf("    fam %2d, CNAME %s, ",
			   ai->ai_family, ai->ai_canonname ? ai->ai_canonname : "<none>");
		if (Curl_printable_address(ai, buf, sizeof(buf)))
			printf("%s\n", buf);
		else
			printf("failed; %s\n", Curl_strerror(conn, SOCKERRNO));
	}
}
#else
#define dump_addrinfo(x,y)
#endif

/*
 * Curl_getaddrinfo() when built ipv6-enabled (non-threading and
 * non-ares version).
 *
 * Returns name information about the given hostname and port number. If
 * successful, the 'addrinfo' is returned and the forth argument will point to
 * memory we need to free after use. That memory *MUST* be freed with
 * Curl_freeaddrinfo(), nothing else.
 */
Curl_addrinfo *Curl_getaddrinfo(struct connectdata *conn,
								const char *hostname,
								int port,
								int *waitp)
{
	struct addrinfo hints;
	Curl_addrinfo *res;
	int error;
	char sbuf[NI_MAXSERV];
	char *sbufptr = NULL;
	char addrbuf[128];
	int pf;
	struct SessionHandle *data = conn->data;

	*waitp = 0; /* don't wait, we have the response now */

	/*
	 * Check if a limited name resolve has been requested.
	 */
	switch (data->set.ip_version)
	{
	case CURL_IPRESOLVE_V4:
		pf = PF_INET;
		break;
	case CURL_IPRESOLVE_V6:
		pf = PF_INET6;
		break;
	default:
		pf = PF_UNSPEC;
		break;
	}

	if (pf != PF_INET)
	{
		/* see if we have an IPv6 stack */
		curl_socket_t s = socket(PF_INET6, SOCK_DGRAM, 0);
		if (s == CURL_SOCKET_BAD)
		{
			/* Some non-IPv6 stacks have been found to make very slow name resolves
			 * when PF_UNSPEC is used, so thus we switch to a mere PF_INET lookup if
			 * the stack seems to be a non-ipv6 one. */

			pf = PF_INET;
		}
		else
		{
			/* This seems to be an IPv6-capable stack, use PF_UNSPEC for the widest
			 * possible checks. And close the socket again.
			 */
			sclose(s);
		}
	}

	MEMSET(&hints, 0, sizeof(hints));
	hints.ai_family = pf;
	hints.ai_socktype = conn->socktype;

	if ((1 == Curl_inet_pton(AF_INET, hostname, addrbuf)) ||
			(1 == Curl_inet_pton(AF_INET6, hostname, addrbuf)))
	{
		/* the given address is numerical only, prevent a reverse lookup */
		hints.ai_flags = AI_NUMERICHOST;
	}
#ifdef HAVE_GSSAPI
	if (conn->data->set.krb)
		/* if krb is used, we (might) need the canonical host name */
		hints.ai_flags |= AI_CANONNAME;
#endif

	if (port)
	{
		snprintf(sbuf, sizeof(sbuf), "%d", port);
		sbufptr = sbuf;
	}
	error = Curl_getaddrinfo_ex(hostname, sbufptr, &hints, &res);
	if (error)
	{
		infof(data, "getaddrinfo(3) failed for %s:%d\n", hostname, port);
		return NULL;
	}

	dump_addrinfo(conn, res);

	return res;
}
#endif /* !USE_THREADING_GETADDRINFO && !CURLRES_ARES */
#endif /* ipv6 */

